Chapter 6 Flashcards
What type of disturbances activate fence disturbance sensors?
Cutting or moving the wires
How do fence electric field or capacitance sensors differ from fence disturbance sensors?
They activate when an intruder approaches the wires due to a change in capacitance coupling.
How is the sensor activated in taut wire sensors?
By deflection in the wires
What initiates a signal in fiber optic cable sensors in the fence disturbance category?
Light wave disturbances (micro-bending)
What can defeat fence disturbance sensors?
Bridging over or tunneling under the fence
What is the detection range of fence electric field or capacitance sensors in terms of distance beyond the wires?
3.3 feet (1 m)
How can sensor fences be less likely to have a high nuisance alarm rate?
By good grounding of the electric sensors
What considerations should be taken into account for designing a control workstation?
Adjustable lighting, temperature, humidity, noise, and comfort features to reduce fatigue and frustration.
Where are displays typically located in a control workstation?
In the center of the console, not requiring much head or eye movement.
How can audible signals be used to alert the operator in a control workstation?
Different pitches and sounds to distinguish various types of alarms.
What can a Graphical User Interface (GUI) improve in a control workstation?
The display of security alarm information.
What are some rules mentioned for designing control workstations regarding color usage?
Limiting colors to 7, using consistent shades for menus/buttons, and considering color-blindness.
What is contraband and give examples of contraband materials?
Materials not permitted in an area, such as weapons, explosives, drugs, recording devices.
What is the main advantage of using manual searches for contraband detection?
Low cost compared to other detection methods.
Why might metal detection be an important part of contraband detection?
It can detect weapons made of steel, a common material choice.
What is a magnetometer used for in contraband detection?
To monitor the Earth’s magnetic field and detect changes.
What are some limitations of using metal detection for contraband detection?
Inability to detect non-ferromagnetic metals like copper, aluminum, zinc.
What is the wavelength of infrared energy used in active infrared sensors?
About 0.9 microns.
How does an active infrared sensor reduce vulnerability to intruders jumping over or crawling under the detection beams?
By forming a ‘fence-like’ beam pattern with multiple aligned beams.
What are some vulnerabilities of active infrared sensors?
Vulnerable to fog, snow, dust storms, can be defeated by various tactics.
What type of energy does Exterior Passive Infrared (PIR) detect?
Changes in heat (thermal energy) in the protected area.
What is important for mounting Exterior Passive Infrared sensors to maintain detection capabilities?
Mounting the sensors where intruders will cross them.
What is a drawback of Exterior Dual Technology sensors?
Individual technology detection probability reduced.
How is the combined detection probability calculated for a dual-technology sensor?
Multiply the individual technology detection probabilities.
What kind of sensors are Video Motion Detection (VMD)?
Passive, covert, line-of-sight sensors processing video signals.
Why is quality of video signal important for Video Motion Detection sensors?
It determines the effectiveness of the sensor.
What are some vulnerabilities of Video Motion Detection sensors in exterior applications?
Susceptible to fog, rain, vibrations, wind, snow, animals, birds.
What is the purpose of an Electron Capture Detector (ECD)?
It determines trace explosives in a vapor sample based on nitro compound affinity.
How is Gas Chromatography (GC) coupled with ECD useful?
It helps identify the type of explosive present in the sample.
What are three benefits of using ECD with GC?
LC,
S and
D of …….
Low cost,
specificity, and
detection of small particle amounts.
Describe the analysis time and maintenance of ECD.
Long analysis times (minutes) and requires frequent maintenance.
What technology is considered the gold standard for detection?
Mass Spectrometry (MS).
How does Mass Spectrometry process ions?
Using magnetic and electrical fields to determine mass-to-charge ratio.
What is the downside of Mass Spectrometry technology?
High cost and difficulty in maintenance.
How does Ion Mobility Spectrometry (IMS) differ from Mass Spectrometry?
IMS operates at atmospheric pressure while MS operates under vacuum.
Why is Mass Spectrometry considered highly specific?
Due to its low limits of detection and specificity.
What does Fluorescence technology use to detect explosives?
Fluorescent polymers that change fluorescence in their presence.
What is a downside of using the Fluorescence technology?
Not all explosives will produce a response.
How do Trace Detection Portals collect samples for analysis?
By agitating a person’s skin and clothes with bursts of air.
What is the screening time range for Trace Detection Portals?
Between 10 to 25 seconds.
What are three downsides of Trace Detection Portals?
High costs,
maintenance requirements, and
large size of units.
What are some applications of Canine Olfaction?
Used in law enforcement and the military for detecting drugs and explosives.
What factors affect the reliability of canines used for detection….5 things?
Vigilance,
skill,
Training
health, and
disposition of the canine….
How do chemical detection sensors differ from biological sensors?
Chemical sensors must detect quickly for attack response, while biological sensors filter and analyze.
What are chemical detectors mainly used for?
Sampling air at perimeter locations to detect threats.
How do biological sensors operate in detecting agents?
Filter air for hours, then analyze samples for several more hours.
What challenges may arise with biological agent exposure and detection?
Exposure may have already occurred by the time the agent is identified.
What technology do microwave sensors use?
Microwave sensors use Doppler shift technology.
Where are microwave sensors often mounted?
Microwave sensors are often mounted near the ceiling of the protected area.
What are some advantages of microwave detection?
Reliability,
low cost, and
high PD.
What are some disadvantages of microwave sensors?
Extra considerations must be taken due to various surfaces and mounting challenges.
How can nuisance alarms be generated with microwave sensors?
Nuisance alarms can be generated from adjacent areas if not limited in coverage.
What should not be used in the detection zone of microwave sensors?
Fluorescent lights should not be used in the detection zone of these sensors.
What type of sensor is an Interior Active Infrared sensor?
Line sensors that operate visibly.
What technology do most Interior Dual Technology sensors combine?
Most combine microwave and passive infrared technology.
How do Interior Dual Technology sensors reduce false alarms?
Both sensors must activate for an alarm to initiate using an AND gate.
Where should ultrasonic sensors ideally be installed?
Ultrasonic sensors should be installed in rooms or areas with infrequent access.
What type of sensors are bistatic microwave sensors considered to be?
Active, visible, and line of sight sensors.
How are bistatic microwave sensors activated?
They are activated when there is a change in energy in ‘the field of view’.
What 3 things can reduce the effectiveness of bistatic microwave sensors?
Overgrown vegetation,
wind, and
standing water.
Where are the antennae typically installed for bistatic microwave sensors?
Between 18 to 24 inches (46 to 60 cm) high from the ground level or sensor bed.
What type of technology is used by monostatic microwave sensors?
Doppler shift technology.
What do monostatic microwave sensors use to limit coverage?
A variable range cut-off circuit.
What are the advantages of monostatic microwave detection?
Reliable, low cost, and highly effective detection properties.
What surfaces can pose extra considerations for monostatic microwave sensors?
Various surfaces used.
How should monostatic microwave sensors be mounted?
They must be mounted to a rigid surface.
What can High Energy X-ray technology calculate?
High Energy X-ray technology can calculate mass, density, and mass absorption coefficient.
What is the purpose of Low-Dose Backscatter X-ray?
Low-Dose Backscatter X-ray detects objects that may be on individuals because it can see beneath clothing.
What are the key components of Nuclear Technologies for detecting explosives?
Nuclear Technologies use gamma rays or neutrons to detect explosives, with TNA determining nitrogen content and PFNA identifying carbon and oxygen content.
What does Quadrupole Resonance (QR) technology detect?
Quadrupole Resonance (QR) technology detects nitrogen-rich materials found in bulk explosives.
How does Raman Analysis function in detecting materials?
Raman Analysis uses laser interrogation and light analysis as a spectroscopic technique.
What is the primary function of Infrared Technology in security?
Infrared Technology may be useful in detecting explosives found on persons.
What is the purpose of Ion Mobility Spectrometry (IMS) in explosive detection?
IMS separates ions by mobility and has high sensitivity to dynamite, TNT, and other explosives.
How does Colorimetry detect the presence of explosives?
Colorimetry uses chemical reactions causing color changes to indicate the presence of explosives.
What does Chemiluminescence use to detect compounds?
Chemiluminescence uses photochemical detection to detect nitro-based compounds.
What are the steps comprised in the installation, maintenance, and repair of IDS components?
Design engineering,
choosing quality components,
professional installation,
commissioning,
auditing,
maintenance, and
repair.
What should be tested and documented during the commissioning of an IDS?
Every device and automated function of the IDS should be tested and documented.
What are the key focus areas during maintenance of IDS systems?
“Randy’s Very Smart About Operations”
• R - Regular maintenance
• V - Visual inspection for calibration
• S - Sensitivity
• A - Alignment
• O - Operational tests for detection zone coverage
How often should batteries be replaced in wireless sensors?
Wireless sensors need to have batteries replaced every 2 to 5 years depending on usage.
What is the purpose of an Alarm Communications and Display (AC&D) system?
Transport alarm signals,
assessment information to a central point,
present information to a human operator,
collect alarm data, and
enable system control.
What are the 2 critical elements of an AC&D system?
Transportation and communication of data, presentation or display of information to a human operator.
Why is reliability crucial in AC&D systems?
Reliability ensures no loss of data, reliable communication, and uninterrupted information display.
What information should an operator console display in an AC&D system?
Zones alert instantly
Z – Zone status and location
• A – Alarm time
• I – Instructions for response or action required
What are passive sensors?
Sensors that produce no signals from transmitters but detect energy emitted in proximity.
Describe the detection capability of passive sensors.
They can detect vibration, heat, sound, capacitance, changes in the environment.
Explain the difference between passive and active sensors.
Passive sensors have no transmitters, detect emitted energy. Active sensors transmit energy.
What is the purpose of overt sensors?
They can act as a possible deterrence by being visible to an intruder.
How do covert sensors differ from overt sensors?
Covert sensors are hidden from view, harder to detect.
What type of sensor may be better for a covert application?
A volumetric sensor due to its ability to be buried.
Explain the difference between Line of Sight (LOS) and Terrain-Following (TF) sensors.
LOS sensors require a clear line of sight, while TF sensors follow terrain.
What type of terrain is suitable for Line of Sight sensors?
Flat terrain as it requires a clear line of sight for detection.
Describe the detection zone of a terrain-following sensor.
It uses transducer elements and radiated fields to create uniform detection.
What is unique about volumetric sensors?
They cover a volume of space making it difficult for intruders to determine coverage boundaries.
Explain Line Detection sensors.
They detect along a line, like when installed with a fence.
How does the environment affect sensor choice?
Characteristics and capabilities play a significant role in choosing sensor type.
Name the three main types of applications for intrusion detection sensors.
Big friendly fence
“Big Friendly Fence”
• Big → Buried Line Sensors
• Friendly → Fence-Associated Sensors
• Fence → Freestanding Sensors
How far below the ground surface should pressure and seismic sensors be installed?
At least 2-3 feet for optimum performance.
What are magnetic field sensors primarily used to detect?
Changes in the magnetic field, typically used for detecting vehicles.
What are the three main types of glass break sensors?
1) Vibratory,
2) Acoustical, and
3) Metallic foil
How do vibratory glass break sensors detect glass breaking?
They detect the shock of breaking glass using jiggle switches, inertia switches, or piezoelectric elements.
How do acoustical glass break sensors operate?
They operate on audible and ultrasonic frequencies above 20 kHz using microphone transducers.
What is the purpose of metallic foil sensors in glass break detection?
Metallic foil sensors use metallic tape on glass to trip a low voltage circuit upon breakage.
How do fiber optic sensors detect intrusion?
They detect disturbances in the fiber optic cable’s tubular light pattern (micro-bending).
What type of detection do electromechanical sensors like door contacts use?
They use line detection for intrusion detection.
What kind of magnetic switch is suitable for low security applications?
A reed switch is suitable for low security applications.
What is a balanced magnetic switch (BMS) and its role in medium security?
A BMS uses a bias magnet to prevent adversarial defeat and is ideal for medium security.
What type of switch requires power but offers high security?
A Hall Effect switch requires power and offers a high level of security.
Where are continuity or break wire sensors often installed?
They are often installed in walls, floors, ceilings, vents, and storage cabinets.
What are the three main components of an Intrusion Detection System (IDS)?
Sensors, annunciators, communications/transmission mechanism.
What are four key considerations for matching IDS elements to a system’s purpose?
Cool measures support operations
Cool Measures Support Operations.”
• Cool → Cost-effective
• Measures → Meets security needs
• Support → Supports operations
• Operations → Operate effectively with subsystems
What are the three main characteristics of intrusion sensor performance?
Probability of Detection (PD), Nuisance Alarm Rate (NAR), Vulnerability to Defeat.
What does the Nuisance Alarm Rate (NAR) signify in an IDS?
Any alarm not caused by an adversary.
How is Vulnerability to Defeat measured in intrusion sensors?
From 0.0 to 1.0.
What are the two ways an adversary can defeat an intrusion sensor?
Bypass or spoof the sensor.
When - 5 ways - should alarms be generated in an IDS?
During adversarial action, condition changes,
power loss,
tampering, and
sensor failure.
What temperature range should an IDS be capable of operating in for indoor units?
32°F to 120°F (0°C to 49°C).
Why is having a continuous line of detection around the perimeter important?
Increases reliability, detection, and provides redundancy.
What is the purpose of using complementary sensors in an IDS?
As an alternate to dual-technology sensors to enhance detection capabilities.
What technology emits fixed frequency pulses?
Pulsed-field technology.
What does continuous wave technology enhance detection of?
Objects of small size like gold.
Why is continuous wave technology ideal for identifying small objects?
It uses a higher than usual frequency.
What happens when a metallic object is present in a pulsed-field detector?
An eddy current is produced and phase detected.
What do handheld metal detectors require the use of?
Security personnel.
Why are same-sex screeners recommended for handheld metal detectors?
To avoid intrusiveness during screening.
What areas should metal detectors be placed near?
Small amounts of steel and other metals.
What are active interrogation methods used for detecting contraband?
X-Ray and Commuted Tomography (CT).
Why are active interrogation methods considered unsafe for humans?
Due to radioactive emissions.
What does X-ray technology often search for?
Materials with low-atomic numbers.
What does a single energy transmission X-ray detector produce?
An image for operator inspection.
Why may conventional X-ray detectors not penetrate heavy metals?
They lack sufficient energy.
What methods can be used for explosive detection?
Bulk technologies and trace methods.
What variables are measured using bulk methodologies for explosive detection?
X-ray absorption coefficient, X-ray backscatter coefficient, etc.
What does dual energy measure in bulk explosive detection?
The mass absorption coefficient.
What are some causes of nuisance alarms in Video Motion Detection systems?
Causes include insects, mice, moving objects, poor lighting, and low contrast camera output.
What are the differences between analog and digital Video Motion Detection systems?
Analog VMDs cost less, while digital VMDs have fewer nuisance alarms.
How can the effectiveness of capacitance proximity sensors be reduced?
Humidity can reduce the effectiveness of capacitance proximity sensors.
What is the required force applied to pressure sensor mats for operation?
5 to 20 pounds of force per square foot (24.4 to 97.6 kg sq. m).
How can Pressure sensors be used to enhance protection?
Pressure sensors can be combined with other technologies for increased protection.
What is the purpose of integrating IDS with video surveillance systems for assessment?
To reduce assessment time; video surveillance towers can be used for video assessment.
What are some challenges of deploying immature technology prematurely?
It can create additional risks to the organization; technology maturity levels should be considered.
What are the eight levels of deploying an effective maturity model for security technologies?
They range from Research to Nontechnical maturity factors such as procedural challenges.
Why are bistatic and monostatic microwave sensors not complementary?
They have the same vulnerabilities to defeat.
Explain how an OR gate functions in sensor combination.
Generates an alarm if one sensor detects an event, increasing PD and NAR.
How does an AND gate differ from an OR gate in sensor integration?
Requires both sensors to trigger for an alarm, reducing both PD and NAR.
Why should an intrusion detection system (IDS) include tamper-protection?
To prevent unauthorized access and ensure system integrity.
What is the purpose of line supervision in an IDS?
To detect when communication lines are cut or altered.
Why is it important for exterior intrusion detection sensors to be protected against electrical surges and lightning strikes?
To ensure system reliability and prevent damage.
